The word "warhater" may be a strong term to describe someone who detests war. Among the possible synonyms are pacifist, peace lover, anti-war activist, war opponent, and peacekeeper. A pacifist is someone who believes in the peaceful resolution of conflicts and opposes war and violence as a means to achieve peace. A peace lover shares the pacifist ideals of peaceful living and avoiding hostilities. An anti-war activist actively protests against wars and engages in campaigns to prevent them from happening. A war opponent is someone who opposes or objects to war and who seeks to prevent or stop it. Finally, a peacekeeper is someone who works to maintain peace and stability and prevent conflicts from escalating into war.